Device for straightening up deformed metal and/or plastic elements after undergoing an excessive mechanical stress

ABSTRACT

The invention relates to a device for straightening up deformed metal and/or plastic elements after having undergone an excessive mechanical stress such as, for example, a shock. It comprises at least one supporting element ( 1 ) provided with means ( 17  to  20 ) for temporarily fixing, to the rigid structure of the vehicle and/or its body, a counter-brace element to which an actuator ( 14 ) may be fastened, said actuator being optionally provided with a jig ( 16 ) or the like and a positionally and/or orientationally adjustable mechanical linkage between said supporting element ( 1 ) and said counter-brace element, this linkage being designed so that at least a fraction of the force exerted by the actuator ( 14 ) on the counter-brace element is retransmitted onto the supporting element ( 1 ).

The present invention relates to an apparatus for straightening outdeformed or even damaged metal and/or plastic members, as a result of aexcessive mechanical stress such as for example an impact.

It is notably but not exclusively applied to the straightening out of abody member of a motor vehicle, deformed for example as a result of anaccident.

Generally, it is known that for carrying out such straightening-out,different solutions are proposed at the present time.

Thus, notably, according to a process currently used by body repairers,a portion of the deformed metal sheet is exposed and small studs,recessed on a point of their periphery, are welded on the latter. Atool, one hook-shaped end of which is engaged into the recess of a stud,is then used. This tool is provided with a slide hammer with whichhammer blows may be given on the end of the tool opposite to the hook,in order to carry out traction pulses on the metal sheet in order tocause its straightening. After having completed the straightening out,the studs are removed by means of the tool, by performing a rotation,and the weld spot is removed, for example with a deburring disc, andfiller is applied to the metal sheet. This solution proves to berelatively long and delicate to perform. Further, it leads tosubstantial reduction in the thickness of the metal sheet, and thereforeto its embrittlement.

With the purpose of simplifying this straightening-out process, withoutaltering the coatings of the metal sheet such as paint, primer,galvanization or electrolytic galvanization, the Applicant has proposeda method consisting of exerting on the deformed member a pressuregenerated by an actuator, a balloon or the like, inflated by means of afluid, the pressure of which is controlled. This method further involvestwo jigs having the original shape of the deformed member which sandwichsaid deformed member. One of these jigs is placed inside the deformedmember while the other one is positioned on the outside of the latter.

It is found that in its present embodiment, this method is difficult toapply to all the portions of an automotive vehicle body.

This notably depends on the fact that the rigid structure of the vehiclebody does not always comprise members on which the actuators or balloonsused by this method may be supported, opposite to the surface, thestraightening out of which is desired.

The object of the invention therefore is more particularly to solve thisproblem.

For this purpose, it proposes an apparatus involving at least onesupporting member equipped with means for temporary fastening onto therigid structure of the vehicle and/or its body, a counter-brace memberon which may be fastened an actuator optionally equipped with a jig orthe like and a mechanical link which may be adjusted in position and/orin orientation between said supporting member and said counter-bracemember, this connecting member being designed so as to retransmit ontothe supporting member at least one fraction of the force exerted by theactuator on the counter-brace member.

Preferably, the aforesaid actuator may be of the pneumatic type andcomprise a pneumatic actuator, an inflatable balloon or bellows or thelike.

The invention particularly advantageously applies to thestraightening-out of deformations of the body top (roof) of a motorvehicle, in particular but not exclusively, deformations due to hail: itis known that during certain thunderstorms, hailstones with relativelylarge dimensions are formed, the impacts of which on a body cause amultiplicity of deformations in the form of pits. The straightening-outof a body having undergone such damage is very long and costly: theprice of the repair may be greater than the price of the vehicle, sothat very often, the owner abandons the idea of having his car repairedif he is not properly insured.

With the invention it is possible to solve this problem by means oftooling of the aforesaid type wherein:

-   -   the supporting member consists in an extensible frame including        two parallel girders, this frame being equipped with hooking        and/or hanging means on the side reinforcements of the body top        (roof) of the vehicle;    -   the connecting member comprises a translationally mobile        cross-bar on both girders of the supporting member;    -   the counter-brace member comprises a column, preferably        adjustable in length, on one of the ends of which said actuator        may be attached, and including, at its other end, a mobile        carriage guided along said cross-bar.

By means of this arrangement, the extensible frame may be positionedinside the vehicle and hung from the side reinforcements of the bodytop, substantially parallel to the latter.

The counter-brace member bearing the actuator equipped with a jig may bebrought at right angles of each deformation by sliding the cross-baralong the girders and the carriage along the cross-bar.

The actuator is then fed with pressurized fluid in order to allow thejig to bring the metal sheet back to its initial shape. This process maybe easily repeated in order to carry out the straightening-out of allthe deformations present on the body top. Considering the nature of thedeformations produced by hail, this type of straightening-out issufficient for bringing the body top back to its initial shape withouthaving to carry out any additional treatment. The cost of the repair istherefore considerably reduced and becomes acceptable, even in the caseof a vehicle with a not very high value. With this solution it ispossible to straighten out members which are impossible to straightenout with conventional tools. Of course, it may be useful for other(notably vertical) portions of the body of a vehicle.

According to another embodiment of the invention, the supporting membermay comprise means for fastening it to the body such as a suction cup oreven a permanent magnet (or even an electromagnet) as well as a columnon which a carriage may slide and be locked, carriage on which a leverprovided with a handle is jointed. On this lever which forms theaforesaid connecting member, a counter-brace member is slidably mounted,on which an actuator optionally equipped with a jig may be fastened. Ofcourse, the lever may be of any order.

Optionally, the connecting member may comprise two branches jointedthrough one of their ends, both branches bearing at their other ends twosupporting parts, at least one of which forms a jig, an actuator beingpositioned between both branches so as to be able to have them pivotaround the joint axis.

Embodiments of the invention will be described hereafter, asnon-limiting examples, with reference to the appended drawings wherein:

FIG. 1 is a schematic perspective view of an apparatus suitable forstraightening-out deformations of a body top of a vehicle;

FIGS. 2 and 3 respectively illustrate in a transverse and elevationalsectional view, an extensible cross-bar which may be used in theembodiment illustrated in FIG. 1;

FIG. 4 illustrates a jointed extensible connecting member which may bemounted on a tubular structure;

FIG. 5 is an alternative embodiment of an apparatus according to theinvention using a circular magnet as a supporting member;

FIG. 6 is a sectional view illustrating the mounting of an actuator on aball-joint counter-brace member;

FIG. 7 illustrates an apparatus according to the invention involving alever;

FIG. 8 is an alternative embodiment of the apparatus according to theinvention specially adapted to the straightening-out of deformations ofa vehicle wing;

FIG. 9 is a side view showing an apparatus involving two levers jointedto each other through one of their ends.

In the example illustrated in FIG. 1, the apparatus is more particularlyintended for straightening out deformations produced on a roof orvehicle body top for example by impacts of hailstones of largedimensions.

This apparatus involves an extensible frame 1 with a square orrectangular shape intended to be positioned inside the vehicle, underthe body top or the roof.

In this example, the sides C₁ to C₄ of the frame 1 each comprise twosegments T₁, T₂ which telescopically engage into each other, thesesegments T₁, T₂ may be tubular or even consist in profiles with a closedand/or open section.

Locking means (not shown) may be used for locking both segments makingeach side C₁ to C₄ with the desired length.

By these arrangements, it is therefore possible to adjust the length ofthe sides C₁ to C₄ and therefore the section of the frame 1 to thedimensions of the inner volume of the vehicle and/or of the body top,the straightening-out of which is desired.

On both opposite sides of the frame 1, an extensible cross-bar TE isslidably mounted, on which a carriage 6 slides, the length of thiscross-bar being adapted to the dimensions of the frame.

In the example illustrated in FIGS. 2 and 3, this cross-bar TE comprisestwo tubular segments 7, 8 of rectangular section which telescopicallyfit into a third tubular segment 9, the outer section of the segments 7and 8 being slightly smaller than the inner section of the third segment9.

This cross-bar may be removable and used independently of the frame inorder to serve as a support for an actuator/jig assembly which may beused in locations such as for example inside a car door.

The carriage as for it consists in a segment with a substantiallyC-shaped profile 10 delimiting a sectional volume slightly larger thanthe outer section of the segment 9.

This profile segment 10 is provided on its face (core) opposite to itslongitudinal aperture 11, with a threaded rod 12, with an axisperpendicular to the plane of the frame 1, on which a column 13 bearinga pneumatic actuator 14 or even directly the pneumatic actuator may beattached. The face of the actuator 14 opposite to the column 13 isitself provided with a rod 15 which extends coaxially with the column 13and which supports a jig 16 used for straightening out the body roof.

The fastening of the frame onto the rigid structure of the vehicle isobtained with four hooks 17-20 respectively positioned at the fourangles of the frame 1.

These hooks 17-20 are intended to be introduced into bore holes or edgespresent in the structure or specially made for this purpose.

Of course, the invention is not limited to this arrangement: the hooks17-20 may be replaced with rods of adjustable length, cables or evenchains. The hooking-up of these rods, cables or chains on the fixedstructure of the vehicle may be achieved by any known hooking and/orfastening means.

The application of this apparatus is particularly efficient: once theframe 1 is installed in the vehicle, the operator may bring the actuator14/jig 16 assembly into a suitable location (under a deformation) bydisplacing the extensible cross-bar TE along the sides and the carriage6 along the cross-bar TE. After having carried out a height adjustmentof this assembly, he proceeds with admission of pressurized gas,preferably compressed air, into the actuator 14. Under the effect of thepressure of the gas, the jig 16 will exert a thrust on the deformationuntil it again assumes its initial shape.

The operator then repeats these operations on the other deformationsuntil the body top or roof is totally straightened out.

Optionally, the cross-bar TE may be jointed so as to allow modificationsof the orientation of the actuator 14 and better adaptation of the jigto the shape of the metal sheet which is intended to be straightenedout.

Thus, FIG. 4 shows a cross-bar TE′ comprising a central member formed byfitting two tubular segments 21, 22 into each other. Both ends of thiscentral member are connected to guiding and/or fastening members 23, 24via two respective joints 25, 26. These guiding and/or fastening members23, 24 consist in a profile segment with a section shaped as an invertedΩ, both ends of which are provided with bore holes into which clampingscrews 27, 28 engage.

On the central member, a carriage 29 intended to bear an actuator 30,for example of the type of the one described earlier, is slidablymounted. Axial blocking of this carriage 29 both as well as that of thetwo tubular segments is ensured by means of respective cone-point setscrews with knurled heads 31, 32.

The guiding and/or fastening members 23, 24 may be slidably mounted onboth parallel sides of a frame 1 of the type of the one illustrated inFIG. 1 or even of a cradle, or even on the structure of the vehicle. Thefixing in position of these guiding members 23, 24 on the frame orcradle is obtained by carrying out tightening of the screws 27, 28.

In the example illustrated in FIG. 5, the apparatus consists of aring-shaped magnetized structure 34 (a ring-shaped permanent magnet orone or several permanent magnets mounted on a ring-shaped structure).This ring-shaped member 34 bears a coaxial cylindrical drum 35 with anouter diameter substantially equal to the inner diameter of thering-shaped structure 34. This drum 35 comprises a bottom 36 and acircular aperture 37 opposite to the bottom 36, this aperture 37 beinglocated at the height of the application face of the ring-shaped member34.

Inside the drum 35, a pneumatic actuator with bellows 38 bearing uponthe bottom 36 is housed and bears, opposite to the bottom 36, a rod 39equipped with a jig 40 of circular shape provided with a slightly convexsupporting face 41.

The adjustment of the height of the jig 40 is obtained by the fact thatthe rod 39 is threaded in its lower portion and will be screwed into atapped tubular sleeve 42 coaxial with the actuator 38 and firmlyattached to the face of the latter opposite the bottom.

In order to straighten out a deformation 43 on a metal (ferromagnetic)sheet 44, the ring-shaped member 34 is applied onto the metal sheet,coaxially with the deformation 43. After having optionally adjusted theposition of the jig 40 by screwing/unscrewing the rod 39 in the sleeve42, it is then proceeded with admission of pressurized gas into theactuator 38. The jig 40 then exerts on the deformation 43 a forcetending to straighten it out. Because of its convex shape, the jig 40may bring the metal sheet slightly beyond its original position bygenerating within the metal sheet a mechanical stress capable ofunfolding possible folds. When admission of the pressurized fluid intothe actuator 38 is interrupted, the slightly convex metal sheet portion(contrary to the initial deformation) returns to its original position,by its elasticity.

Advantageously, the apparatus illustrated in FIG. 5 may be mounted on aframe like the actuator illustrated in FIG. 1.

In the example illustrated in FIG. 7, the apparatus involves a lever 45one of the ends of which bears a handle 46 while the other end isjointed on a tubular sleeve 47 slidably mounted on a rod 48 firmlyattached through one of its ends to a suction cup 49 (or even a magnetor electromagnet).

Along this lever 45, a carriage 50 is slidably mounted, formed by atubular segment on which a pneumatic actuator 52 bearing a jig 53 may befastened via an attachment column 51. Blocking of the carriage 50 in aposition on the lever 45 is ensured by means of the cone-point set screw54 which will be screwed into a tapped bore hole provided on thecarriage 50.

By these arrangements, with view to straightening out a deformation of ametal sheet, the suction cup 49 is attached onto a metal sheet portionwhich may consist but not necessarily in the metal sheet bearing thedeformation.

By sliding the carriage 50 along the lever 45 and by optionally havingthe latter pivot, the jig 53 borne by the apparatus 52 is broughtagainst the deformation. The actuator 52 is then actuated so that thejig exerts a force on the deformation until the sought straightening-outis obtained. This force is spread by the suction cup 49 and by theoperator who exerts an antagonistic force on the handle 46 of the lever45.

Optionally, in order to allow better adjustment of its orientation, theactuator used in the examples described earlier may be mounted on itssupport (counter-brace member) via a ball joint connection.

This solution is illustrated in FIG. 6, wherein the actuator 60 (of thebellow type) is mounted in a tubular body 61 at least partly closed onone side by a bottom 62 firmly attached to an end of the actuator 60.The other end of the actuator 60 is extended with a threaded rod 63emerging from the body 61 through a coaxial orifice and on which rod ajig 64 will be able to be screwed in.

The bottom 62 bears a tapped coaxial tubular sleeve 65 into which therod 66 of a ball joint 67 may be screwed ensuring a ball jointconnection with a supporting part 68, which may for example consist in acarriage of the type of those used in the previous examples.

An advantage of this solution consists in that the operator may hold thetubular body in his/her hand while having his/her hand protected bycircular coaxial flanges with which the ends of said body are equipped.

The apparatus illustrated in FIG. 8 is specially designed forstraightening out deformations produced on a wing 70 of an automobile.It involves a lever 71 bent at right angles bearing at one of its ends,a handle 72 and at its other end, a jig 73, optionally interchangeable(in order to be adapted to the shape to be straightened out).

This lever 71 is jointed at its bend by a clevis mounting 74 on asupporting part 75 delimiting a concavity, for example a C-section partinto which the upper portion of the tyre 76 of the vehicle located atthe wing 70 may closely engage. The core 77 of this supporting part 75comprises, opposite to the tyre 76, a plate 78 which extends at rightangles. On this plate 78 is attached an actuator 79, here aconcertina-type actuator, which acts on the arm 80 of the lever 71bearing the jig 73.

In order to straighten out the deformation of the wing 70, the operator,first of all, positions the supporting part 75 on the tyre 76 andfastens it thereto, optionally in the desired angular position, byfastening means not shown. The actuator 79 is then retracted. Theoperator then tips over the lever 71 until the jig 73 will bear upon thewing 70 in the region where the deformation is located: the operatorthen controls the actuation of the actuator 79 by retaining the handle72 until the deformed portion is straightened out.

Optionally, the lever described earlier may be used without the actuatoror even without the supporting part 75.

In the example illustrated in FIG. 9, the apparatus appears as anelongated claw having two arms 81, 82 jointed to each other through anend (joint 83). Both of these arms at their other ends bear tworespective fastening means 84, 85 intended to receive, either asupporting element, or a jig (elements 86, 87).

This claw may be handled by means of a handle 88 borne by a third arm 89jointed around the axis of the joint 83 of the arms 81, 82.

Between both arms 81, 82 is positioned a pneumatic actuator 90 formed byan elastomeric balloon connected to a pressurized gas admission circuit.

Due to its elongated shape, this apparatus may be engaged in narrowpassages, for example between the metal sheet of the body and thestiffeners associated with this metal sheet.

Of course, the invention is not limited to the embodiments describedearlier.

Thus, for example, the actuator may further comprise means with whichvibrations may be generated facilitating the return of the deformedmetal sheet to its initial position.

These vibrations may be obtained by variable frequency percussion.

Also, the jig may be mounted on the actuator via an easilyconnectable/disconnectable fastening device such as for example aVelcro™ fastener.

Further, the member for supporting the apparatus according to theinvention may involve a plastic foam cushion bearing upon a structuralmember of the vehicle. The density of the foam (for example polyurethanefoam) will be provided so as to ensure transmission of the forces whilefollowing the shape of the supporting part. Better distribution of thepressures exerted on this supporting part is then achieved. Moreover,the travel of the actuator will be shortened.

1. An apparatus for straightening out plastic and/or metal membersdeformed as the result of an excessive mechanical stress such as forexample an impact, comprising at least one supporting member equippedwith temporary fastening means on the rigid structure of the vehicleand/or of its body, a counter-brace member on which may be fastened apneumatic actuator optionally equipped with a jig or the like exerting athrust on the deformation of the members to be straightened out, and amechanical link adjustable in position and/or in orientation betweensaid supporting member and said counter-brace member, this connectionmember being designed so as to retransmit onto the supporting member atleast one fraction of the force exerted by the actuator on thecounter-brace member.
 2. The apparatus according to claim 1, wherein theaforesaid actuator comprises a pneumatic actuator, an inflatable balloonor bellows or the like.
 3. The apparatus according to claim 1, wherein:the supporting member consists of an extensible frame including twoparallel girders this frame being equipped with hooking and/or hangingmeans on the side reinforcements of the body top (roof) of the vehicle;and the connecting member forms the adjustable mechanical link comprisesa translationally mobile cross-bar on two segments of each girder of thesupporting member.
 4. The apparatus according to claim 3, wherein thecounter-brace member comprises a column on one of the ends of which maybe fastened said actuator, and including at its other end, a mobilecarriage guided along said cross-bar.
 5. The apparatus according toclaim 4, wherein the aforesaid column is adjustable in length.
 6. Theapparatus according to claim 3, wherein said temporary fastening meansare positioned at the four angles of the aforesaid frame and comprisehooks, rods of adjustable length, cables or chains capable of beingintroduced into bore holes or edges present in the rigid structure ofthe vehicle or of its body.
 7. The apparatus according to claim 3,wherein the sides of the frame each comprise two segments telescopicallyengaging into each other, these segments may be tubular or even consistin profiles with a closed and/or open section.
 8. The apparatusaccording to claim 7, comprising locking means capable of locking bothsegments making each of the sides, with the desired length.
 9. Theapparatus according to claim 3, wherein the aforesaid cross-barcomprises two tubular segments of rectangular section whichtelescopically fit into a third tubular segment, the outer section ofthe segments being slightly smaller than the inner section of the thirdsegment, and wherein the carriage comprises a substantially C-shapedprofile segment, delimiting a volume with a section slightly greaterthan the outer section of the segment.
 10. The apparatus according toclaim 9, wherein the profile segment forming the aforesaid carriage isprovided on its face (core) opposite to its longitudinal aperture, witha threaded rod, with an axis perpendicular to the plane of the frame, onwhich a column bearing a pneumatic actuator may be fastened.
 11. Theapparatus according to claim 3, wherein the aforesaid cross-bar isjointed so as to allow modifications of the orientation of the actuatorand better adaptation of the jig to the shape of the metal sheetintended to be straightened out.
 12. The apparatus according to claim11, wherein the aforesaid cross-bar comprises a central member formed byfitting two tubular segments into each other, both ends of this centralmember being connected to guiding and/or fastening members via tworespective joints.
 13. The apparatus according to claim 12, wherein theaforesaid guiding and/or fastening members have substantially a shape ofan inverted Ω, both ends of which are provided with bore holes intowhich engage clamping screws.
 14. The apparatus according to claim 12,wherein on the central member a carriage is slidably mounted, intendedto bear an actuator, the axial blocking of this carriage as well as thatof the two tubular segments being ensured by means of respectivecone-point set screws with a knurled head.
 15. The apparatus accordingto claim 3, wherein the aforesaid cross-bar is removable and is designedso as to be able to be used independently of the frame.
 16. Theapparatus according to claim 1, comprising a ring-shaped magnetizedstructure bearing a cylindrical drum comprising a bottom and a circularaperture located opposite the bottom, at the height of the applicationface of the ring-shaped member, this drum housing an actuator bearingupon said bottom and bearing a jig opposite to said bottom.
 17. Theapparatus according to claim 16, wherein the aforesaid jig is mounted onthe actuator by means of a threaded rod which will be screwed into atapped tubular sleeve firmly attached to a face of the actuator oppositeto the bottom.
 18. The apparatus according to claim 1, wherein theaforesaid jig has a slightly convex supporting face so as to bring themetal sheet to be straightened out to beyond its original position. 19.The apparatus according to claim 1, wherein the supporting membercomprises means for fastening to the body, such as a suction cup or evena permanent magnet (or even an electromagnet), these fastening meansbeing firmly attached to a column on which a carriage may slide and belocked on which is jointed a lever provided with a handle, and in thaton this lever which forms the aforesaid connecting member, acounter-brace member is slidably mounted, on which may be fastened anactuator optionally equipped with a jig.
 20. The apparatus according toclaim 1, characterized in that wherein the aforesaid actuator is mountedon the counter-brace member, via a ball joint connection.
 21. Theapparatus according to claim 1, characterized in that wherein theaforesaid actuator comprises an actuator including a tubular body whichmay be held by hand, this body having ends provided with flanges usedfor protecting the hand of the operator.
 22. The apparatus according toclaim 1, for straightening-out deformations produced on a wing of avehicle, comprising a bent lever bearing at one of its ends a handle andat its other end, a jig, this lever being jointed at its bend on asupporting part delimiting a concavity intended for receiving the upperportion of the tyre of the vehicle located at said wing, the core ofthis supporting part comprising, opposite the tyre, a plate on which isfastened an actuator which acts on the arm of the lever bearing the jig.23. The apparatus according to claim 1, wherein the actuator comprisesmeans allowing vibrations so as to facilitate the return of the metalsheet to its initial position.
 24. The apparatus according to claim 25,wherein the aforesaid vibrations are obtained by percussion at avariable frequency.
 25. The apparatus according to claim 1, wherein thejig is mounted on the actuator via an easily connectable/disconnectablefastening means, comprising a hook and loop fastener.
 26. The apparatusaccording to claim 1, wherein the supporting member includes a plasticfoam cushion, designed for following the shape of a supporting part andensuring better distribution of the forces on this supporting part.